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45-623: The X-Ray Imaging and Spectroscopy Mission ( XRISM , pronounced "crism"), formerly the X-ray Astronomy Recovery Mission ( XARM ), is an X-ray space telescope mission of the Japan Aerospace Exploration Agency (JAXA) in partnership with NASA to provide breakthroughs in the study of structure formation of the universe , outflows from galaxy nuclei , and dark matter . As the only international X-ray observatory project of its period, XRISM will function as

90-613: A 13-year blank period in soft X-ray observation, until the launch of ATHENA in 2035. This would result in a major setback for the international community, as studies performed by large scale observatories in other wavelengths, such as the James Webb Space Telescope and the Thirty Meter Telescope will commence in the early 2020s, while there would be no telescope to cover the most important part of X-ray astronomy. A lack of new missions could also deprive young astronomers

135-719: A chance to gain hands-on experience from participating in a project. Along with these reasons, motivation to recover science that was expected as results from Hitomi , became the rationale to initiate the XRISM project. XRISM has been recommended by ISAS's Advisory Council for Research and Management, the High Energy AstroPhysics Association in Japan, NASA Astrophysics Subcommittee, NASA Science Committee, NASA Advisory Council. With its successful launch in September 2023, XRISM

180-554: A deep survey for black holes a billion times more massive than the Sun, to investigate how particles are accelerated to very high energy in active galaxies , and to understand how the elements are created in the explosions of massive stars by imaging supernova remnants . Having completed a two-year primary mission, NuSTAR is in its twelfth year of operation. NuSTAR's predecessor, the High Energy Focusing Telescope (HEFT),

225-573: A five-month implementation feasibility study. In January 2005, NASA selected NuSTAR for flight pending a one-year feasibility study. The program was cancelled in February 2006 as a result of cuts to science in NASA's 2007 budget. On 21 September 2007, it was announced that the program had been restarted, with an expected launch in August 2011, though this was later delayed to June 2012. The principal investigator

270-627: A focal length of 5.6 m (18 ft). Resolve is an X-ray micro calorimeter developed by NASA and the Goddard Space Flight Center . The instrument is a duplicate version of its Hitomi predecessor. It used some space-qualified hardware left from the manufacture of Hitomi 's SXS. Xtend is an X-ray CCD camera. Xtend improves on the energy resolution of Hitomi 's SXI. JAXA launched XRISM on 6 September 2023 at 23:42 UTC (7 September 08:42 Japan Standard Time) using an H-IIA rocket from Tanegashima Space Center . XRISM

315-608: A group at the Danish Technical University . The shells were then assembled, at the Nevis Laboratories of Columbia University, using graphite spacers machined to constrain the glass to the conical shape, and held together by epoxy. There are 4680 mirror segments in total (the 65 inner shells each comprise six segments and the 65 outer shells twelve; there are upper and lower segments to each shell, and there are two telescopes); there are five spacers per segment. Since

360-450: A high-density and low-density material); with NuSTAR's choice of Pt/SiC and W/Si multilayers, this enables reflectivity up to 79 keV (the platinum K-edge energy). The optics were produced, at Goddard Space Flight Center , by heating thin (210 μm (0.0083 in)) sheets of flexible glass in an oven so that they slumped over precision-polished cylindrical quartz mandrels of the appropriate radius. The coatings were applied by

405-687: A next generation space telescope in the X-ray astronomy field, similar to how the James Webb Space Telescope , Fermi Space Telescope , and the Atacama Large Millimeter Array (ALMA) Observatory are placed in their respective fields. The mission is a stopgap for avoiding a potential period of observation loss between the current X-ray telescopes ( Chandra and XMM-Newton ), and those of the future ( Advanced Telescope for High Energy Astrophysics (ATHENA)). Without XRISM, there could be

450-561: A telescope in space. Spitzer's proposal called for a large telescope that would not be hindered by Earth's atmosphere. After lobbying in the 1960s and 70s for such a system to be built, Spitzer's vision ultimately materialized into the Hubble Space Telescope , which was launched on April 24, 1990, by the Space Shuttle Discovery (STS-31). This was launched due to many efforts by Nancy Grace Roman, "mother of Hubble", who

495-508: A time period during with no X-ray data was collected. This would arise in the early 2020s as these two reach the end of their missions, due to the loss, in 2016, of the Hitomi X-ray telescope, which was launched to be the follow-on to the Chandra and Newton telescopes. During its early design phase, XRISM was also known as the " ASTRO-H Successor " or " ASTRO-H2 ". After the loss of Hitomi ,

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540-600: A total of 12 arcminutes field of view (FoV) for each focal plane module. The cadmium zinc telluride (CdZnTe) detectors are state of the art room temperature semiconductors that are very efficient at turning high energy photons into electrons . The electrons are digitally recorded using custom application-specific integrated circuits (ASICs) designed by the NuSTAR California Institute of Technology (CalTech) Focal Plane Team. Each pixel has an independent discriminator and individual X-ray interactions trigger

585-550: Is Fiona A. Harrison of the California Institute of Technology (Caltech). Other major partners include the Jet Propulsion Laboratory (JPL), University of California, Berkeley , Technical University of Denmark (DTU), Columbia University , Goddard Space Flight Center (GSFC), Stanford University , University of California, Santa Cruz , Sonoma State University , Lawrence Livermore National Laboratory , and

630-459: Is analogous to Hitomi 's hard X-ray instruments. Once XRISM 's operation starts, collaborative observations with NuSTAR will likely be essential. Meanwhile, the scientific value of the soft and hard X-ray band width boundary has been noted; therefore the option of upgrading XRISM 's instruments to be partially capable of hard X-ray observation is under consideration. A hard X-ray telescope proposal with abilities surpassing Hitomi

675-520: Is expected to cover the science that was lost with Hitomi , such as the structure formation of the universe, feedback from galaxies/active galaxy nuclei, and the history of material circulation from stars to galaxy clusters. The space telescope will also take over Hitomi 's role as a technology demonstrator for the European Advanced Telescope for High Energy Astrophysics (ATHENA) telescope. Multiple space agencies, including NASA and

720-474: Is ignored. NuSTAR has demonstrated its versatility, opening the way to many new discoveries in a wide variety of areas of astrophysical research since its launch. In February 2013, NASA revealed that NuSTAR, along with the XMM-Newton space observatory, has measured the spin rate of the supermassive black hole at the center of the galaxy NGC 1365 . By measuring the frequency change of X-ray light emitted from

765-533: Is limited by the filtering and distortion of electromagnetic radiation ( scintillation or twinkling) due to the atmosphere . A telescope orbiting Earth outside the atmosphere is subject neither to twinkling nor to light pollution from artificial light sources on Earth. As a result, the angular resolution of space telescopes is often much higher than a ground-based telescope with a similar aperture . Many larger terrestrial telescopes, however, reduce atmospheric effects with adaptive optics . Space-based astronomy

810-493: Is more important for frequency ranges that are outside the optical window and the radio window , the only two wavelength ranges of the electromagnetic spectrum that are not severely attenuated by the atmosphere. For example, X-ray astronomy is nearly impossible when done from Earth, and has reached its current importance in astronomy only due to orbiting X-ray telescopes such as the Chandra X-ray Observatory and

855-671: The Chandra X-ray Observatory . Each focusing optic has its own focal plane module, consisting of a solid state cadmium zinc telluride (CdZnTe) pixel detector surrounded by a cesium iodide (CsI) anti-coincidence shield . One detector unit — or focal plane — comprises four (two-by-two) detectors, manufactured by eV Products . Each detector is a rectangular crystal of dimension 20 × 20 mm (0.79 × 0.79 in) and thickness ~2 mm (0.079 in) that have been gridded into 32 × 32 × 0.6 mm (1.260 × 1.260 × 0.024 in) pixels (each pixel subtending 12.3 arcseconds) and provides

900-499: The European Space Agency (ESA) are participating in the mission. In Japan, the project is led by JAXA's Institute of Space and Astronautical Science (ISAS) division, and U.S. participation is led by NASA's Goddard Space Flight Center (GSFC). The U.S. contribution is expected to cost around US$ 80 million, which is about the same amount as the contribution to Hitomi . The X-ray Imaging and Spectroscopy Mission will be one of

945-493: The Italian Space Agency (ASI). NuSTAR's major industrial partners include Orbital Sciences Corporation and ATK Space Components . NASA contracted with Orbital Sciences Corporation to launch NuSTAR (mass 350 kg (770 lb)) on a Pegasus XL launch vehicle on 21 March 2012. It had earlier been planned for 15 August 2011, 3 February 2012, 16 March 2012, and 14 March 2012. After a launch meeting on 15 March 2012,

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990-765: The Soviet space program (later succeeded by Roscosmos of Russia). As of 2022, many space observatories have already completed their missions, while others continue operating on extended time. However, the future availability of space telescopes and observatories depends on timely and sufficient funding. While future space observatories are planned by NASA, JAXA and the CNSA , scientists fear that there would be gaps in coverage that would not be covered immediately by future projects and this would affect research in fundamental science. On 16 January 2023, NASA announced preliminary considerations of several future space telescope programs, including

1035-512: The XMM-Newton observatory . Infrared and ultraviolet are also largely blocked. Space telescopes are much more expensive to build than ground-based telescopes. Due to their location, space telescopes are also extremely difficult to maintain. The Hubble Space Telescope was serviced by the Space Shuttle , but most space telescopes cannot be serviced at all. Satellites have been launched and operated by NASA , ISRO , ESA , CNSA , JAXA and

1080-404: The titanium-44 isotope concentrated in clumps at the remnant's center and points to a possible solution to the mystery of how the star exploded. When researchers simulate supernova blasts with computers, as a massive star dies and collapses, the main shock wave often stalls and the star fails to shatter. The latest findings strongly suggest the exploding star literally sloshed around, re-energizing

1125-532: The Great Observatory Technology Maturation Program, Habitable Worlds Observatory , and New Great Observatories. NuSTAR NuSTAR ( Nuclear Spectroscopic Telescope Array , also named Explorer 93 and SMEX-11 ) is a NASA space-based X-ray telescope that uses a conical approximation to a Wolter telescope to focus high energy X-rays from astrophysical sources, especially for nuclear spectroscopy , and operates in

1170-513: The Resolve instrument (equivalent to Hitomi 's soft X-ray spectrometer), as well as Xtend (SXI), which has a high affinity to Resolve. The elimination of a hard X-ray telescope was justified by the 2012 launch of NASA's NuSTAR satellite, something that did not exist when Hitomi (then known as the New X-Ray Telescope, NeXT) was initially formulated. NuSTAR's spatial and energy resolution

1215-519: The X-ray spectrum from the accretion disk winds, NuSTAR and XMM-Newton observed heating and cooling cycles of the relativistic winds leaving the accretion disk . NuSTAR and XMM-Newton detected X-rays emitted behind the supermassive black hole within Seyfert 1 galaxy I Zwicky 1. Upon studying the flashes of light emitted by the corona of the black hole, researchers noticed that some detected light arrived to

1260-449: The black hole corona, NuSTAR was able to view material from the corona be drawn closer to the event horizon . This caused inner portions of the black hole's accretion disk to be illuminated with X-rays, allowing this elusive region to be studied by astronomers for spin rates. One of NuSTAR's main goals is to characterize stars' explosions by mapping the radioactive material in a supernova remnants . The NuSTAR map of Cassiopeia A shows

1305-514: The detector housings. The crystal shields, grown by Saint-Gobain , register high energy photons and cosmic rays which cross the focal plane from directions other than the along the NuSTAR optical axis. Such events are the primary background for NuSTAR and must be properly identified and subtracted in order to identify high energy photons from cosmic sources. The NuSTAR active shielding ensures that any CZT detector event coincident with an active shield event

1350-403: The detector later than the rest, with a corresponding change in frequency . The Stanford University team of scientists that led the study concluded that this change was directly attributable to radiation from the flash reflecting off of the accretion disk on the opposing side of the black hole. The path of this reflected light was bent by the high spacetime curvature, directed to the detector after

1395-406: The epoxy takes 24 hours to cure, one shell is assembled per day – it took four months to build up one optic. The actual telescope consists of two separate Focal Plane Modules (FPMs) labelled FPMA and FPMB. These two FPMs are built to be similar, though they are not identical. Depending on the source and on the observation, one of the modules will usually report higher counts. This is corrected for in

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1440-446: The exact relative positions of the optics and the focal plane at all times, so that each detected photon can be mapped back to the correct point on the sky even if the optics and the focal plane move relative to one another during an exposure. Each focusing optic consists of 133 concentric shells. One particular innovation enabling NuSTAR is that these shells are coated with depth-graded multilayers (alternating atomically thin layers of

1485-556: The first projects for ISAS to have a separate project manager (PM) and primary investigator (PI). This measure was taken as part of ISAS's reform in project management to prevent the recurrence of the Hitomi accident. In traditional ISAS missions, the PM was also responsible for tasks that would typically be allocated to PIs in a NASA mission. While Hitomi had an array of instruments spanning from soft X-ray to soft gamma ray, XRISM will focus around

1530-505: The launch was pushed further back to allow time to review flight software used by the launch vehicle's flight computer. The launch was conducted successfully at 16:00:37 UTC on 13 June 2012 about 117 mi (188 km) south of Kwajalein Atoll . The Pegasus launch vehicle was dropped from the L-1011 'Stargazer' aircraft . On 22 June 2012, it was confirmed that the 10 m (33 ft) mast

1575-446: The name XARM was used, the R in the acronym refers to recovering the ability to do X-ray spectroscopy and its benefits. The name changed to XRISM in 2018 when JAXA formally initiated the project team. With the retirement of Suzaku in September 2015, and the detectors onboard Chandra X-ray Observatory and XMM-Newton operating for more than 15 years and gradually aging, the failure of Hitomi meant that X-ray astronomers would have

1620-455: The range of 3 to 79 keV . NuSTAR is the eleventh mission of NASA's Small Explorer (SMEX-11) satellite program and the first space-based direct-imaging X-ray telescope at energies beyond those of the Chandra X-ray Observatory and XMM-Newton . It was successfully launched on 13 June 2012, having previously been delayed from 21 March 2012 due to software issues with the launch vehicle. The mission's primary scientific goals are to conduct

1665-484: The readout process. On-board processors, one for each telescope, identify the row and column with the largest pulse height and read out pulse height information from this pixel as well as its eight neighbors. The event time is recorded to an accuracy of 2 μs relative to the on-board clock. The event location, energy, and depth of interaction in the detector are computed from the nine-pixel signals. The focal planes are shielded by cesium iodide (CsI) crystals that surround

1710-599: The satellite. The XARM pre-project preparation team was formed in October 2016. In the U.S. side, formulation began in the summer of 2017. In June 2017, ESA announced that they would participate in XARM as a mission of opportunity. XRISM carries two instruments for studying the soft X-ray energy range, Resolve and Xtend. The satellite has telescopes for each of the instruments, SXT-I (Soft X-ray Telescope for Imager) and SXT-S (Soft X-ray Telescope for Spectrometer). The pair of telescopes have

1755-433: The science results step, usually by apply a constant multiplier during spectral fitting and light curve analysis. The expected point spread function for the flight mirrors is 43 arcseconds , giving a spot size of about two millimeters at the focal plane; this is unprecedentedly good resolution for focusing hard X-ray optics, though it is about one hundred times worse than the best resolution achieved at longer wavelengths by

1800-594: The stalled shock wave and allowing the star to finally blast off its outer layers. In January 2017, researchers from Durham University and the University of Southampton , leading a coalition of agencies using NuSTAR data, announced the discovery of supermassive black holes at the center of nearby galaxies NGC 1448 and IC 3639. In March 2nd of 2017, NuSTAR published an article to Nature detailing observations of wind temperature variations around AGN IRAS 13224−3809 . By detecting periodic absences of absorption lines in

1845-451: Was a balloon-borne version that carried telescopes and detectors constructed using similar technologies. In February 2003, NASA issued an Explorer program Announcement of Opportunity (AoO). In response, NuSTAR was submitted to NASA in May 2003, as one of 36 mission proposals vying to be the tenth and eleventh Small Explorer missions. In November 2003, NASA selected NuSTAR and four other proposals for

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1890-404: Was fully deployed. Unlike visible light telescopes – which employ mirrors or lenses working with normal incidence – NuSTAR has to employ grazing incidence optics to be able to focus X-rays. For this two conical approximation Wolter telescope design optics with 10.15 m (33.3 ft) focal length are held at the end of a long deployable mast. A laser metrology system is used to determine

1935-423: Was proposed in 2017. The FORCE (Focusing On Relativistic universe and Cosmic Evolution) space telescope is a candidate for the next ISAS competitive medium class mission. If selected, FORCE would be launched after the mid-2020s, with an eye towards conducting simultaneous observations with ATHENA. Following the premature termination of the Hitomi mission, on 14 June 2016 JAXA announced their proposal to rebuild

1980-613: Was successfully inserted into orbit on the same day, and the accompanying launch payload, SLIM , began its multi-month journey to the Moon. A protective shutter over the Resolve instrument's detector has failed to open. This does not prevent the instrument from operating, but limits it to observing X-rays of energy 1800  eV and above, as opposed to the planned 300 eV . A similar shutter over Xtend has opened normally. Space telescope In 1946, American theoretical astrophysicist Lyman Spitzer , "father of Hubble" proposed to put

2025-608: Was the first Chief of Astronomy and first female executive at NASA. She was a program scientist that worked to convince NASA, Congress, and others that Hubble was "very well worth doing". The first operational space telescopes were the American Orbiting Astronomical Observatory , OAO-2 launched in 1968, and the Soviet Orion 1 ultraviolet telescope aboard space station Salyut 1 in 1971. Performing astronomy from ground-based observatories on Earth

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